Central Processing Units (CPUs) of computers generate large quantities of heat during operation, especially as the speed of operation increases. However, this heat, if confined in the computer housing, can affect the operation and reliability of many heat sensitive elements forming parts of the computer, including the CPU itself, motherboard components, memory, CD ROM, CDRW, DVD, hard drive, Disk on Chip, Magnetic media, floppy drives, electronic cards, etc especially in personal computers, industrial computers, servers, workstations, mainframes, other computers and telecommunication devices.
A conventional cooler for cooling an electronic device such as CPU mainly contains a heat sink and a fan. The heat sink is made of copper or aluminum. The heat sink collects heat from the electronic device and the fan blow away the heat collected therefrom. The trend at present is to increase the power of the CPUs, which causes an increase in the temperature inside the computer housing. The conventional cooler sometimes cannot sufficiently remove the heat produced. Accordingly, it is becoming more necessary to find an efficient cooling apparatus.
At present, there is a known device known as thermoelectric cooler (TEC). A thermoelectric cooler includes a cold side and a hot side which, under a voltage difference, pump heat using the Peltier effect. The thermoelectric cooler utilizes electrical current to absorb heat from the cold side of the cooler and dissipate that heat on the hot side (opposite side).
A conventional TEC apparatus comprises a TEC and a heat sink. The cold side of the conventional TEC apparatus contacts a CPU. The TEC transmits the heat collected from the CPU to the heat sink and the heat sink dissipates the heat.
Another conventional TEC apparatus comprises a TEC and a heat sink. The heat sink contacts a CPU and collects heat therefrom. A cold side of the TEC contacts the heat sink and transmitted the heat to a hot side of the TEC and then dissipates the heat to the air.
These devices are very reliable and cost effective in low wattage applications. However, in high wattage applications, a conventional TEC apparatus is less efficient than a conventional non-TEC cooler as illustrated in FIG. 4 (test results.) In FIG. 4, the horizontal axis represents CPU wattage, the vertical axis represents heat resistance, curve C1 represents a non-TEC cooler and curve C2 represents a conventional TEC apparatus. The test results are based on same testing circumstances such as using the same CPU, and the same fan under the same rotating speed (4200 rpm). The lower heat resistance, the more efficient the cooler.
In addition, the conventional TEC apparatuses don't provide detecting temperature sensors directly contacting the CPUs. Therefore, the control circuits thereof cannot receive precise temperature indications, so cannot precisely control the amount of electricity provided to the TECs in accordance with the indication. Accordingly, it would be very desirable to have an efficient thermoelectric cooling apparatus for an electronic device such as a CPU, or a computer chip which does not suffer from the drawbacks of the conventional coolers or the conventional TEC apparatuses.